Biomedical subjects

S Yacoub

Publications and source records attributed to S Yacoub.

13 recordsLinked to original sources

PubMed2004

[Axillary lymphadenectomy with muscular padding, without drainage].

OBJECTIVE: Axillary padding without drainage appeared to be a valuable alternative technique to vacuum drainage. The technique employs local muscles or the axillary aponeurosis for padding. We report here the clinical evaluation of muscular padding without drainage. The analysis of these results prompted us to also do a literature search for other alternatives aimed at reducing morbidity due to vacuum drainage. PATIENTS AND METHODS: Muscular padding was prospectively performed by 8 different surgeons on a total of 152 patients at the Centre Rene-Huguenin (Saint-Cloud, France). Follow-up has attained 3.5 years. A comparative assessment of pain was conducted in 30 patients operated on with vacuum drainage. RESULTS: This technique is easy to learn and reproducible. It facilitates post-operative follow-up, always allowing discharge at the 2nd or 3rd post-operative day without any home nursing. The late sequels are not increased. In contrast, pain was twice more intense during the first post-operative weeks compared with vacuum drainage, and the seroma rate was also increased. DISCUSSION AND CONCLUSION: Despite good efficacy, this worsening of pain is a major obstacle to the routine use of muscular padding. A technical improvement has been published very recently where the axillary aponeurosis was used to pad the axilla. It seems to be equally efficient but less painful than muscular padding. This technique is under clinical evaluation and could appear as a valuable option to vacuum drainage. Other alternatives are discussed. Most studies lack a direct comparison with vacuum drainage and a satisfactory evaluation of quality of life is also omitted. New studies with quality of life scales are ongoing. They should allow us to choose options that take this aspect into account in the future.

Axilla↗

PubMed2003

[Fever-shivers reaction and standard platelet concentrates transfusion: a prospective study].

Fever-shivers reaction (FSR) is the most frequent transfusion immediate incident related to platelet transfusions. The aim of our prospective study was to assess the frequency of the different immediate incidents, especially the frequency and the causes of the FSR, observed during the transfusion of standard platelet concentrates (SPC). For each FSR, analysis of causes included: a bacterial culture of the implicated SPC, a blood culture and HLA antibody screening (lymphocytotoxicity assay) among the patients. In the study period, 34 patients were followed during 74 transfusions. Ten immediate incidents were noted; FSR: N = 8, erythema-urticaria: N = 1 and nausea-vomit: N = 1. The FSR was observed in 6 patients who received 56 SPC. Analysis of causes of this reaction revealed that: HLA antibodies were present in one patient; bacterial contamination was not found neither among the patients nor in the implicated SPC, and the risk of the FSR occurrence rose with increased storage time of the SPC transfused. Indeed, a significant difference was noted between the mean age of the SPC implicated in the FSR and the mean age of those not implicated (P = 0,0028). In conclusion, the FSR is a frequent incident observed during SPC transfusions. In the majority of cases, the cause of this reaction was not identified. Further studies will be necessary to better understand the physiological mechanisms of the FSR.

Adolescent↗

PubMed2003

Treatment of haemophilia A in Tunisia: efficacy and inhibitor study.

Cryoprecipitate is the principal type of factor VIII (FVIII) concentrate used for treating haemophilia A in Tunisia. Allergic reactions, viral transmission, and inhibitor formation remain the most serious complications of FVIII therapy. The aims of the study presented here were to evaluate the efficacy of FVIII therapy, to investigate the inhibitor prevalence, and the factors which may affect inhibitor formation in our haemophilia A patients. Plasma samples were screened for FVIII inhibitors by the Bethesda method. 30 minutes FVIII recovery was also determined for each patient. In this prospective study, 18 previously treated haemophilia A patients, four with severe (FVIII concentration <2%) and 14 with moderate haemophilia, were closely followed up during administration of 223 FVIII concentrates (cryoprecipitate and/or fresh frozen plasma). The median age of the patients involved in the study was 13.5 years (range 5 to 53). Clinical response to FVIII was consistently good to excellent. In the majority of cases, actual and predicted FVIII recovery correlated' well. Adverse reactions were not observed. Five patients, aged less than 18 years and minimally treated (>36 FVIII exposure days), were found to have low titre FVIII inhibitors (<10 Bethesda units) at the end of the study. Inhibitor activity was detected in one patient with severe and in four patients with moderate haemophilia. In conclusion, FVIII therapy was effective, well tolerated, and low titre inhibitors identified did not preclude continued on demand FVIII therapy. Our study has also demonstrated that patients' age and treatment regimen do not affect inhibitor formation. Further studies are necessary to confirm these findings.

Adolescent↗

PubMed2002

[Transfusion practice and attitudes].

During last years, blood transfusion and transfusion security were domains which have preoccupied health authorities, the population and health professionals. Beginning with the principle that blood transfusion is a care that must be under medical responsibilities, authors analyse physician's implication in this field. To reach this objective, a study interested 199 young physicians, working in two university hospitals in Tunisia. Results indicate that physician's knowledge about blood transfusion is insufficient to guarantee quality of this medical act. In terms of attitudes and practices, physicians are not really always implicated in the different stages of blood transfusion process. Intervention is limited to prescription and blood transfusion record card writing. Transfusion herself and monitoring were, in particular, delegated to nurses. So transfusion incidents were under--declared. Transfusion medicine must occupy important place in physicians curriculum. At hospital level, quality insurance process, based on audit, have to be implemented to obtain transfusion good practices, in a domain were risks are unfortunately not yet totally circumscribed.

Attitude of Health Personnel↗

PubMed2002

[Role of ALAT level in preventing post-transfusional hepatitis. Prospective study of 1,180 blood donors in Tunisia].

In Tunisia, regular serological tests for prevention of blood transmitted hepatitis consist in the research of HBS antigen and HCV antibodies. Our purpose in this study is to estimate the prevalence of hypertransaminasemia in blood-donors and to determinate to what extent it could prevent blood-transmitted hepatitis. Therefore we have assessed ALAT sera level in 1180 blood-donors. It rate is considered elevated if higher than twofold the normal rate (> N = 40 Ul/l). Donors with high ALAT level were summoned three months later after their blood gift to undergo clinical examination and a new serological test, researching seroconversion of HBS Ag and HCV antibodies. With regarding to estimation of residuel HCV infection risk, we were based on M.P Busch's data. Hpertransaminasemia was modified in 134 individuals (11.5%). Only 67 had replied to our summons. Alcoholism was involved in one case. Smoking was found in most of male donors. We had discovered neither weight excess nor drug or medicines consumption which could explain increasing ALAT. New serological list had revealed seroconversion for HCV antibodies in ELISA but with undeterminated profile in Immunoblot (anti NS5 solely). PCR was not carried out. Residual infection risk being considered, use of hypertransaminasemia detection in blood donors should prevent nearly 1.67 blood transmitted hepatitis per million transfusions units. However if we consider shortage in blood derivates in Tunisia, such a decision should be comprehensively weighted numerous blood donors will be moved aside.

Adolescent↗

PubMed1997

Higher prevalence of parvovirus B19 in Belgian as compared to Tunisian blood donors: differential implications for prevention of transfusional transmission.

Serious anaemia can be induced by human parvovirus B19 (HPV) infection in immuno-compromised patients or subjects with an haemolytic disorder. Routine inactivation procedures are insufficient to neutralize the virus, but screening for HPV is an effective means to avoid transmission by transfusion of blood components. In the present study, we have compared for the first time the IgG and IgM seroprevalence in a North African (Tunisian) and Western European (Belgian) population of blood donors. The prevalence of HPV-specific IgM was less than 2% in both populations, pointing to the absence of an epidemic. The prevalence HPV IgG was significantly (p < 0.01) higher in Belgium (74%) than in Tunisia (65%), without any relationship with age or sex. This finding may suggest a south-north gradient of this infectious disease. Since the presence or absence of HPV-specific antibodies does not preclude transfusional transmission, screening for the virus itself should be done to avoid iatrogenic infection in HPV-naive subjects at risk. In view of the different transfusion policies in Belgium and Tunisia, a strategy for each of both countries is proposed.

Adolescent↗

PubMed1996

Noise of surface bio-potential electrodes based on NASICON ceramic and Ag-AgCl.

The electrochemical noise from dry NASICON-based surface electrodes and pregelled Ag-AgCl electrodes is evaluated in saline solutions and on the skin. The electrochemical noise from the electrode/electrolyte interface is found to be negligible (less than 1 microV peak to peak). On the skin, the noise level is highly dependent on the patient. At high frequencies, the skin/electrode interface noise is equal to 'thermal noise' and can be related to the real part of the skin/electrode impedance. At low frequencies (F < 100 Hz), excess noise is observed that varies as f-2. It is tentatively ascribed to a non-stationary process or noise of electrochemical origin due to the ionic nature of the skin. The contribution of residual EMG signal of low amplitude (5 microV peak to peak) is suggested for electrodes with large surface area.

Ceramics↗

PubMed1994

[Clinical prognostic factors in breast cancer. Retrospective study of 5609 cases].

We studied the clinical factors of metastatic risk of breast cancer in 5609 consecutive cases of unilateral invasive breast cancer, wholly treated and followed at René-Huguenin Center from 1962 to 1988, and without any other cancer (even a controlateral breast cancer). All these patients were protocolary treated; these protocols, especially medical treatments (chimio and hormonotherapy), being modified along with years. At 20 years, the global metastasis free survival was 56%. Clinical size, existence of inflammatory signs, UICC clinical stage, clinical nodal status were highly significant in the Cox multivariate analysis (P < 0.000001). Age (P < 0.0008) and adherence to skin or underlying parietal (P < 0.007) were also but less significant. On the other hand, location of the tumor, time between first signs and diagnosis were not predictive. The women under 35 years had more metastatic locations during their evolution (P < 0.05) and maybe more visceral metastasis (NS).

Adult↗

PubMedDate not supplied

Seroepidemiological survey of rickettsial infections among blood donors in central Tunisia.

In this report we attempt to evaluate the prevalence of antibodies against Rickettsia conorii, R. typhi, Coxiella burnettii, and Ehrlichia chaffeensis in central Tunisia. Five hundred sera from blood donors, collected between March and June 1993, were tested for these 4 antibodies using an indirect immunofluorescence antibody assay (IFA). Nine percent of the sera had antibodies against R. conorii (IgG > 1:32) by IFA, and 8% by Western blotting; with IFA, 3.6% had antibodies to R. typhi, 26% to C. burnetii (> 1:50), and none to E. chaffeensis. Infection rates with R. conorii and R. typhi did not differ significantly between the sexes, but fewer young people had antibodies to R. typhi. A significantly higher prevalence of antibodies to C. burnetii was noted for males with no difference between age classes. No significant difference was detected between urban and rural areas. This study confirmed the endemicity of rickettsioses, and revealed a high seroprevalence of Q fever, in central Tunisia.

Adolescent↗

PubMedDate not supplied

Prevalence of C282Y and H63D mutations in the haemochromatosis (HFE) gene in Tunisian population.

The studies of the HFE mutations: H63D and C282Y in North African populations have revealed the extreme rarity or even the absence of the C282Y mutation. We have examined 1140 chromosomes (570 Tunisian people) for the presence of the two HFE mutations by PCR-RFLP analysis. We have found that the allele frequencies are, respectively, 15.17% (+/-2.1%) for the H63D and 0.09% (+/-0.17%) for the C282Y. These results are consistent with the worldwide spread of the H63D mutation and the north European restriction of the C282Y. This study will be completed by determining whether homozygote trait for H63D and associated risk factors (beta thalassémia) can lead to iron overload in Tunisia.

Female↗

PubMedDate not supplied

[The utility of class I HLA antibodies screening in a Tunisian obstetric department in order to select good HLA typing reagents].

In order to reduce the cost of the serologic class I HLA typing, we have established a screening program for HLA antibodies among obstetric patients. Class I HLA antibodies were identified by standard microlymphocytotoxicity test using a panel of 100 lymphocytes. In the study period, carried out between January 2000 and June 2002, 817 women were tested, most of them (62%) during the last trimester of pregnancy and in the other cases after delivery. These patients, aged between 18 and 45 years, were in the majority (88%) multiparous. From the total number of 817 maternal serum samples screened, 194 specimens (23,74%) tested positive for HLA antibodies. Thirty eight HLA specificities were characterised in 110 maternal sera of which 62 contained monospecific HLA antibodies. HLA-A2 and HLA-B51(5) were the most common specificities characterised in this study. HLA alloimmunization was present since the first pregnancy. There was no statistically significant linear correlation between HLA alloimmunization and the number of pregnancies. Fifty maternal serum samples (6,11%) could be used as HLA typing reagents. Of these 50 sera, 36 had monospecific HLA antibodies. These useful antisera covered a total of 30 specificities: 8 HLA-A and 22 HLA-B. The cost of self - screening for useful antisera as estimated at dollars 62/mL, the personnel was not considered. However, the lowest cost of commercial HLA typing sera is approximately dollars 400/mL. Our study showed the utility and the net economic advantage to use maternal sera as reagents in our new HLA laboratory with limited budget.

Adolescent↗

PubMedDate not supplied

[Quality control of platelet concentrates: experience of Sousse (Tunisia) blood centre].

The aim of this prospective study was to control the quality of platelet concentrates prepared in Sousse blood centre: standard platelet concentrates (SPC) and apheresis platelet concentrates (APC) in order to detect anomalies and apply corrections. The quality control included three parameters: pH, volume, cells count: platelets, residual white blood cells (WBC) and red blood cells (RBC). The SPC pH was measured with pH meter, samples were obtained at the end of shelf-life by the destructive method. The control of SPC cells count was determined with a Beckman coulter, samples were collected by the stripping method. The APC quality control was assessed in the same conditions than those described for SPC but samples were collected by the transfer method. Quality control results were compared to Europe standards. During a period of six months (July-December 2002), 475 SPC (16% of the production) and 36 APC (60% of the production) were controlled. More than 95% of the SPC meet standards in regard to pH, volume and residual WBC count. However, the number of platelets and residual RBC meet standards respectively in 58% and 42% of SPC. All the APC meet standards for the three quality parameters. In conclusion, in order to improve the quality of our SPC, in regard to the number of platelets and residual RBC, two actions are respectively necessary to satisfy requirements: collecting the appropriate volume of whole blood and controlling the separation technique.

Blood Banks↗

PubMedDate not supplied

[Hereditary sideroblastic anemia: a rare diagnosis].

Hereditary sideroblastic anemia is a very rare disease recessive and X-linked that affect heme biosynthesis by deficit or decreased of delta aminolevulinic acid synthase (ALAS) activity. We report a case of a six-month-old boy, admitted in the hospital for anemic syndrome. The hemogram showed anemia (hemoglobin: 4.5 g/dL), frankly hypochronic microcytic and a regenerated (mean corpuscular hemoglobin concentration: 26 g/dL, mean cell volume: 53 fl, reticulocytes: 10 x 10(9)/L) with red cells morphologic disorders in smears (anisopoikylocytosis) without attack of the other lineages; white blood cells: 11 x 10(9)/L (neutrophils: 64% and lymphocytes: 35%); platelets: 350 x 10(9)/L. Examination of bone marrow showed an important erythroid hyperplasia (about 69%) with dyserythropoiesis. Perls stain revealed intense siderosis with 90% of ringed sideroblasts and a large number of siderocytes. Exploration of ALAS2 and ABC7 genes on the DNA of the infant was not found abnormalities. Treatment with pyridoxine corrects moderately the anemia. By the way, we proposed to remind that iron deficiency, inflammatory syndrome and thalassemia are the common microcytic anemia. However, it's mandatory to explore other causes if diagnosis is not solved.

Anemia, Sideroblastic↗